Thermal Vacuum Switch

Fig 41 Thermal Vacuum Switch:

1. Cool the air cleaner assembly to below 40° F.
2. Disconnect vacuum hoses from TVS and connect an external vacuum source to large fitting.
3. Apply vacuum to TVS. If TVS does not hold vacuum, replace it.
4. Start engine and allow air cleaner temperature to rise above 55° F. If vacuum is held by TVS, replace it.